JPS6332302B2 - - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a control station device, particularly a data highway that is located between a data highway and an information processing device connected to the data highway and controls data communication between the two. control station device.

Generally, a control station device receives a received frame in a predetermined format from a data highway, and sends received data included in this received frame to an information processing device.

FIG. 1 is a format explanatory diagram showing an example of a frame format of a received frame received by the present invention and a conventional control station device. The frame format 15 is the control unit 1
6 and a data section 17, the control section 1
6 includes a data length field 18 indicating the data length of the received data constituting the data section 17.

Therefore, the control station device is
When a received frame is received, storage control of the received data and transfer control of the information processing device are performed according to the data length indicated by the data length field 18.

A conventional control station device includes an input buffer for storing received data included in a received frame received from a data highway, and an information processing device for transmitting the received data stored in the input buffer each time the received frame is received. It is configured to include an input/output control section for sending out data.

An example of a conventional control station device will be described below with reference to the drawings.

Figure 2 is a block diagram showing an example of a conventional control station device, which is equipped with one input/output buffer for sending and receiving data, and data sent to and received from the information processing device is sent to each buffer. They were inserted one by one and sent to and received from the data highway.

In the figure, reference numeral 1 indicates a control station device, and its configuration includes an input/output control unit 3 that controls an interface with a data highway 2, an input data buffer 4, and an input/output unit connected to an interface cable 6 with an information processing device 5. It consists of a control section 7, an output data buffer 8, and a common control section 9.

By the way, the data received from the data highway 2 includes, in addition to long data as general information sent from other control station devices,
There is short data such as normal reception notification and non-reception notification, but like long data, this short data is also stored in the input data buffer 4 of the control station device 1 and sent to the information processing device 5 each time.

Therefore, in the information processing device 5 serving as the host, the number of times the short data is received increases, which increases the load on the information processing device 5.

In addition, in a system in which a large number of real-time processing minicomputers, factory terminals, etc. are connected to the data highway 2, short data from these devices is continuously generated and sent to the control station device 1. , the information processing device 5 may not be able to receive it in time, and short data may be dropped.

That is, the conventional control station apparatus has a drawback in that the number of times received data is sent to the information processing apparatus is large.

An object of the present invention is to provide a control station device that can reduce the number of times received data is sent to an information processing device.

That is, an object of the present invention is to solve the above-mentioned drawbacks by determining long data and short data and storing the short data in the control station until a specified time is reached, thereby reducing the number of times the information processing device receives the short data. An object of the present invention is to provide a control station device that can prevent data from being dropped.

When the control station device of the present invention receives a receive frame consisting of a data section and a data length field indicating the data length of this data section from a data highway, the control station device can select whether the data is long data or short data depending on whether the data length is equal to or larger than a predetermined length. a first input data buffer that stores long data when the determination result indicates that the data is long data; and a first input data buffer that stores the long data when the determination result indicates that the data is short data. a second input data buffer that cumulatively stores the short data when the determination result indicates that the data is long; a timer that counts time and generates a timeout signal after a specified time; and an input/output control section that outputs the long data stored when the timeout signal is present and the short data accumulated and stored when the timeout signal is generated to the information processing device.

That is, the control station device of the present invention is a control station device for a data highway that is located between a data highway and an information processing device connected to the data highway and transfers data between the two. In addition to the first input data buffer for storing long data transmitted from the highway, a second input data buffer for storing short data is provided, and when data is received from the data highway, it is determined whether the data is long data or short data. The long data is sent to the first input data buffer and the short data is sent to the second input data buffer.
The long data is stored in the input data buffer of , and the long data is sent to the information processing device each time it is received, and the short data is accumulated and sent to the information processing device at regular intervals.

That is, the control station device of the present invention has a first input data buffer for storing long data and a second input data buffer for storing short data.
input data buffer, and a buffer control unit that controls these two input data buffers.Long data and short data from the data highway are judged by a judgment circuit and input into the respective input buffers, and the timer of the buffer control unit is activated when a specified time elapses. If it is determined that the short data has been stored, the short data is sent from the second input buffer to the information processing device according to instructions from the buffer control section.

Next, embodiments of the present invention will be described in detail with reference to the drawings.

FIG. 3 is a block diagram showing an embodiment of the present invention, in which the control station device 1' includes a determination circuit 12 for determining the length of data received from the data highway 2, and a determination circuit 12 for determining the length of data received from the data highway 2, and for storing the length data after determination. an input data buffer 10 for cumulatively storing short data after determination, an input buffer 11 for cumulatively storing short data after determination, and a buffer control unit 14 including a timer 13 for controlling the two input data buffers and notifying the passage of a specified time.
It consists of: The other parts are the same as those shown in FIG.

Next, the operation of transmitting short data to the information processing device 5 will be described.

Received data from the data highway 2 is received by an input/output control section 3 for the data highway.
The frame format of the received frame is configured as explained in FIG.

Therefore, if the data length shown in the data length field 18 is less than a certain value (for example, 8 bytes), it is considered short data, and if it exceeds that value (for example, 9 bytes or more), it is considered long data. A reception frame received by the input/output control unit 3 is determined by a determination circuit 12 for determining the data length as to whether it is long data or short data, and is input into the corresponding input data buffer.

In the input buffer 11, each time new short data is accumulated, the end mark indicating the end of the accumulated short data is erased, and the end mark is placed at the address immediately after the newly accumulated short data. .

When the timer 13 in the buffer control unit 14 indicates that the specified time has been reached, a timeout signal is generated and the short data accumulated up to the end mark is immediately transferred to the input/output control unit 7 according to the instruction from the buffer control unit 14. The information is transmitted to the information processing device 5 through.

In this case, when the specified time is reached and no short data is stored in the input buffer 11, the buffer control unit 14 does not issue an instruction.

Further, the value of the timer 13 can be set manually or externally by a program.

Note that in the above embodiment, the timer starts counting time from when the first short data is stored.

By adding a second input data buffer and a timer, the control station device of the present invention cumulatively stores short data, performs time counting, and collectively processes the stored short data when a predetermined time has elapsed. Since the received data can be sent to the device, the number of times the received data is sent out can be reduced.

In other words, the control station device of the present invention can greatly reduce the number of times the short data is transmitted to the information processing device by accumulating and storing the short data in the input data buffer until the timer times out, and the short data is stored in the input data buffer until the timer times out. Because it can be temporarily stored in an input data buffer separate from the input data buffer, it has the effect of preventing short data from being lost.

[Brief explanation of the drawing]

FIG. 1 is a format explanatory diagram showing an example of the frame format of a received frame received by the present invention and a conventional control station device, and FIG. 2 is a schematic block diagram including an example of the conventional control station device.
FIG. 3 is a block diagram containing one embodiment of the present invention. 1, 1′...control station device,
2...Data highway, 3...I/O control unit,
4... Input data buffer, 5... Information processing device, 6... Interface cable, 7... Input/output control section, 8... Output data buffer, 9... Common control section, 10... Input data buffer 1, 11
... Input data buffer 2, 12 ... Judgment circuit,
13...Timer, 14...Buffer control unit, 1
5...Frame format, 16...Control unit,
17...Data section, 18...Data length field.

Claims (1)

[Claims] 1 When a received frame consisting of a data section and a data length field indicating the data length of this data section is received from the data highway, it is determined whether the data is long data or short data based on whether the data length is greater than or equal to a predetermined length. a first input data buffer that stores the long data when the determination result indicates that the data is long; and a first input data buffer that stores the long data when the determination result indicates that the data is short; a second input data buffer that cumulatively stores short data; a timer that counts time starting from when the first short data is stored and generates a timeout signal after a specified time; and the determination result is long data. and an input/output control unit that outputs the stored long data to the information processing device when the timeout signal is generated, and outputs the accumulated stored short data to the information processing device when the timeout signal is generated. control station equipment.